CVE-2015-4203: Cisco IOS

Medium severity, CVSS 5.4. EPSS: 2.2% chance of exploitation in the next 30 days.

Race condition in Cisco IOS 12.2SCH in the Performance Routing Engine (PRE) module on uBR10000 devices, when NetFlow and an MPLS IPv6 VPN are configured, allows remote attackers to cause a denial of service (PXF process crash) by sending malformed MPLS 6VPE packets quickly, aka Bug ID CSCud83396.

Affected products

• Cisco IOS: version 12.2(33)sch only; version 12.2sch only

Published 2015-06-23. Last modified 2026-06-17.